Blackle: saving the world by painting Google black
Heap Media decided to do something about it by creating a custom version of one of the most popular white-backgrounded sites on the web. Blackle is basically Google, but black. It's powered by Google, so you should have pretty much the same user experience when using Blackle as you do with Google. Only darker.
While there's some debate over whether a black-backgrounded Google will actually make an impact on the world's energy use, the folks behind Blackle say there's another purpose. At the very least, those who use Blackle daily will be reminded to find other ways to reduce energy consumption throughout the day.